Embodiments of the present invention relate to an array substrate, a liquid crystal panel, a liquid crystal display and a driving method thereof.
At present, liquid crystal displays (LCDs) are the most popular flat panel displays, and thin film transistor liquid crystal displays (TFT-LCDs) dominate the market of LCDs. According to the direction of applied electric field, LCDs can be classified into a vertical electric field type LCD, such as twisted nematic (TN) type LCD, and a horizontal electric field type LCD, such as in-plane switching (IPS) type LCD and fringe field switching (FFS) type LCD.
In various types of LCDs, liquid crystal molecules rotate under driving of applied electric field so that light selectively transmits through the layer of the liquid crystal molecules to display at a gray level. The above-mentioned electric field for driving liquid crystal molecules is formed between a pixel electrode and a common electrode. Typically, the common voltage applied to the common electrode keeps constant and the voltage applied to the pixel electrode is controlled by driving signal sequences, so that the electric field formed between the pixel electrode and the common electrode can be changed.
Coupling phenomenon occurs between adjacent pixel units when the electric fields in the adjacent pixel units have the same polarity. In order to decrease the adverse influence of such coupling phenomenon on the display quality, a reverse drive technology is proposed. In the reverse drive technology, the electric fields in the pixel units are alternately reversed by appropriate driving signal sequences between frames of an image, so that the rotation direction of the liquid crystal molecule is alternately changed. For example, the common voltage of the common electrode is set as +6 V and the voltage of the pixel electrode is changed in the range of 0˜+12 V, so that the alternately-reversed electric field can be achieved. With the reverse drive technology, a frame-reverse mode, a row-reverse mode, a column-reverse mode or a point-reverse mode can be achieved. Point-reverse mode is preferred by the manufacturers due to its uniform display image, high image quality and small coupling between adjacent pixel units.